Portable, wheeled tool carts have been available for some time. One such prior art tool cart is shown and described by Wise, the inventor herein, in U.S. Pat. No. 5,642,898 issued Jul. 1, 1997. Additional tool carts have been described in the patent literature. For instance, U.S. Pat. No. 4,955,941, issued Sep. 11, 1990, to Rousseau, describes a support table for a bench saw. U.S. Pat. No. 4,230,329, issued Oct. 28, 1980 to Johnson, describes a mobile cart. U.S. Pat. No. 5,161,590, issued Nov. 10, 1992, to Otto, describes a miter saw table apparatus. U.S. Pat. No. 5,255,724; issued Oct. 26, 1993, to Butke, describes an adjustable extension assembly. A brochure showing the Rousseau SS2850 product discloses a mobile miter saw stand. U.S. Pat. No. 6,886,836 entitled “Counterbalanced Universal Mobile Saw Stand,” issued May 3, 2005 to the inventor herein discloses a built-in handtruck design that enables the end user to transport common table saws and equipment to the location of the project being undertaken. The unit quickly folds out into a fully supporting work bench for actual use of the saw and/or equipment. The saw stand shown in the '836 patent is a significant advance in the art in that the device disclosed therein permits a heavy power saw, such as a table saw to be transported to or from a jobsite on roller wheels in the manner of a conventional handtruck. The saw can then be used with the saw stand in a collapsed position (e.g., low to the ground) or in a raised position at table height. This saw stand has a built-in feature that enables the unit to stand in the vertical position with the saw attached. This creates ease in transporting the unit to and from the workplace, i.e., in elevators, truck beds, etc. Also built into the design is the ability to use the saw in the horizontal stowed position for hardwood floor installers, etc.
This unit is constructed of powder-coated tubular steel and sheet metal. Ergonomic handles and lockout devices are incorporated into each aspect of this unit for ease of use, safety, and product longevity. Quick automatic latch mechanisms are an integral part of the unit for the flip-out support leg and the saw table surface. These latches are automatic in the setup mode and require manual release for returning the unit to the stowed position.
One disadvantage of this prior art design, as well as other prior art designs discussed above, is that when the saw stand is in the extended or raised position, a significant part of the load is borne by the wheels. On a smooth, flat surface (e.g., a garage floor, hardwood floors, etc.) vibrations from the saw tend to cause minor movement in the wheels, thus allowing undesirable vibrations to become amplified through positive feedback and reverberate through the saw stand.
Thus, a need exists for a mobile, collapsible power tool stand that can roll on wheels, but that also lifts the saw stand off the wheels when erected or extended.